Albumin and fibrinogen syntheses increase while muscle protein synthesis decreases in head-injured patients

Am J Physiol. 1997 Nov;273(5):E898-902. doi: 10.1152/ajpendo.1997.273.5.E898.

Abstract

The effect of trauma on protein metabolism was investigated in the whole body, muscle, and liver in severely head-injured patients presenting an acute inflammatory response by comparison to fed control subjects receiving a similar diet. Nonoxidative leucine disposal (an index of whole body protein synthesis) and muscle, albumin, and fibrinogen synthesis were determined by means of a primed, continuous infusion of L-[1-13C]leucine. Nonoxidative leucine disposal increased by 28% in the patients (P < 0.02). Fractional muscle protein synthesis rate decreased by 50% (P < 0.01) after injury. Fractional and absolute fibrinogen synthesis rates were multiplied by two and nine, respectively, after injury (P < 0.001). Albumin levels were lower in patients (25.2 +/- 1.2 g/l, means +/- SE) than in controls (33.7 +/- 1.2 g/l, P < 0.001). However, fractional albumin synthesis rates were increased by 60% in patients (11.4 +/- 1.0%/day) compared with controls (7.3 +/- 0.4%/day, P < 0.01). Therefore, 1) head trauma induces opposite and large changes of protein synthesis in muscle and acute-phase hepatic proteins, probably mediated by cytokines, glucocorticoids, and other stress hormones, and 2) in these patients, hypoalbuminemia is not due to a depressed albumin synthesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blood Proteins / metabolism
  • Calorimetry
  • Craniocerebral Trauma / metabolism*
  • Energy Metabolism
  • Fibrinogen / biosynthesis*
  • Humans
  • Leucine / metabolism*
  • Liver / metabolism*
  • Muscle, Skeletal / metabolism*
  • Proteins / metabolism*
  • Reference Values
  • Serum Albumin / biosynthesis*

Substances

  • Blood Proteins
  • Proteins
  • Serum Albumin
  • Fibrinogen
  • Leucine